Coffer-dam.



I. B. LIBBEY1 COPPER. DAM. APPMGATION FILED JUNE 25. 1912.

Patented Apr. 1, 1913.

2 SHBETS-SHBET l.

www Zw/ annum) I. B. LIBBEY.

GOFIBB. DAM.

APPLICATION FILED JUNE 25. 1912.

Patented Apr. 1, 1913.

2 SHEETS-SHEET 2.

o o o L6@ ISAIAH is. LIBBEY, or cnnaLorrEsvILLn, iIimIIaIa.`

T all whom it may conce/mf Be it known that LISAIAH B. LIBBEY, a

citizen of the United States, residingI at Charlottesville, in the county of Albemarle and State of Virginia, have invented new and useful Improvements in Cotter-Dams, of which the ollowin is a specification.,

The invention has or its object to su ply a structure of the nature specified w 'ch cilitated by may be placedin position with despatch and which may be removed after the work has been performed, said removal being fathe particular construction which admits of the lock joints being released rom vthe interior preliminary to abandoning the interior prior-to separating the sections when taking the device. apart. Y The invention consists of the novel fea- Y tures, details of construction. and combinay the appended claims.

tion of parts, which hereinafter willbe more particularly set forth, illustrated in the accompanying drawings, and pointed out in Referrin to the drawings, forming a part of the specification, Figure 1' is a side view of a coii'erdam lembodying the invention. Fig. 2 is a vert-ical section thereof on the line 2-2 of Fig. 3. Fig. 3 is a horizontal section on the line 3-3 of Fi 1. Fig. 4

is a det-ail perspective view. o one of the plates or sections prior tobeing curved. Fig.` 5 is a detail rspictive view of thel edge portions of ad3acent plates or sections,

showing the locking strips,the plates being separated and iiat. Fig. 6 is'a horizontal section on'the line 6--6 of Fig. 5.

Corresponding and like parts are referred to in the following deseri tion, and indicated'in all the views of t e drawings, by the same reference characters.

The structure embodies a plurality of piles 1, which are set in position at the place where the pier or other structure is to be erected. A skeleton framework is placed in position about the piles 1 and comprises a series of rings 2, which are placed one above the other and held in position by tie rods 3. The rings 2 are of angle :formation in Vcross section, one of the wings or anges having a vertical arrangement and the other being disposed horizontally. .The vertical.-

A Speeication of Letters Patent. Application led Iune 25,1 912. Serial' No. 705,812.

' .PatentedApr.1,1913.

or sections 4, whereas the horizontal wings have been placed in position 'a ring, is arranged toencirele the upper ends of the iles 'and the lower ends of the first set o tie wings or flanges support the inclosing plate I' or anges receive tie rods. After the piles rods are fastened thereto, after which the ring is lowered and a second ring placed in position and secured to the upper ends of the tie rods. The tie rods have end portions threaded for a short distance and -receivea Vpair of nuts between which the horizontal wings or anges of the/rings are clamped.-

After the second ring has been secured to the Aes ends of the rst set of tie rods a second setA 'l of tie rods is secured to the second ring,

after which the structure is lowered and a third ring placed in position-and secured to the upper ends of the second set of tie rods when a third set of tie'rods are secured to the third ring. The skeleton structure is similarly-formed untilVV of the required. length, the structure bein lowered step bystep as each ring is place in position and made scf cure. `For lowering the structure a tackle 5 is provided and fitted to the upper ends of selected piles, as indicated in Fig. 1. After the skeleton structure has been constructed and lowered into place the inclosing sections or plates'4 are placed in position about said structure. The plates or sections 4 constitute elements of the shell'orl inclosing walls of the cofferdam and are braced and strengthened by the skeleton structure, the latter sustaining the external pressure of the water after the 'coerdam has been pumped' out. lThe sections 4 consist of metal plates of suitable width and of 'a len h corre- I spending to the height of the /col erdam so that thelr lower ends may penetrate the b ed of the water and their upper portion `project above the level of the water at high tide. Strips 6 are placed upon opposite sides of a vertical edge portion of each plate or secltion 4 and aresecured thereto by rivets or fastenings 7*. The strips 6 project a short distance from the vertical edge of the plate or section so as to form a space 7 which receives the vertical edge portions of the adl jacent section or a mating-joint isV ormed between 'the abutlate 4. In this manner ting edge portions of adjacent plates or sections.

Locking strips 8 and 9 are secured to vertical edge portions of each plate or section 4 and their outer edges are recurved, as indicated at l() and l1 so as to interlock and retain the sections in place. The lock strips 8 and 9 are secured at their inner edges to the plates 4 and curve outwardly from said plates toward their outer edges so as to form spaces opposite the joints bet-Ween the plates or sections 4 when said sections are placed together and the outer recurved edges of the locking strips are in engagement'. These spaces are indicated most clearly in Fig. 3 and are adapted to receive a cement or concrete 12, whereby the joints between the sections or plates 4 are made tight so as tol exclude the passage of water. f

The locking strips are secured to the outer sides of the plates 4 and are attached thereto in a manner' to admit of their ready removal and for this purpose bolts 13 are employed -as the fastening means, the heads of the bolts facing inward. The locking strips have threaded openings to receive the threaded ends of the bolts or fastenings 13, as indicated most clearly in Fig. 6. The sections are prevented from inward movement by reason of their edges abutting and outward movement is prevented by the interlocking of the recurved edge portions l0 and ll with the locking plates. Lateral displacement of the abutting ends of the plates or' sections 4 is prevented by the strips 6, which embrace opposite sides of the edge portions of adjacent plates. The plates or sections 4 are slipped into position from above with the vertical edge of one plate passing into the space 7 of the plate already in position and with the recurved edge portions of the locking strips in engagement, the plate lowering being assisted in its descent by a driver such as employed for driving the piles into the bed of the body of water. After the cofferdarn has been set up cement or concrete is forced into the spaces l2` to render the joints tight and after the cement has set the water is pumped from the cofferdam in the usual manner `to admit of the work being performed. AAfter the pier has been constructed or the required work performed the fastenings securing the locking strips to the shell of the eoitferdam are loosened and the locking strips S and 9 removed, thereby admitting of the sections or plates 4 being easily removed. The skeleton structure is elevated step-by-step, each of the rings being removed in succession together with the tie rods in the reverse order practised in assembling said parts.,

From the foregoing description, taken in connection with the accompanying drawings, the advantages of t-he construct-ion and l. A coiferdam comprising an outer shell i and an inner supporting structure of skeleton form and comprising rings and sets of tie rods.

2. A coiferdam comprising an outer shell and an inner supporting structure of skeleton form and comprising rings 'and sets of tie rods, each of said rings consisting of a vertical flange and a horlzontal flange, the

latter having openings and the tie rods be-y ing arranged topass throu h the openings in the horizontal flanges o the rings and serving to connect the same in series.

3. In a coderdam and in combination with an inclosing shell, a supporting structure of skeleton form arranged within the shell and comprising superposed rings and tie rods, each of the rings comprisingavertical flange and a horizontal flange, the latter having openings to receive thel tie rods, the latter having their end portions threaded and receiving pairs of nuts, a set of tie rods being provided for each two rings.

4. In a cofferdam, a shell formedpf ver tically arranged plates having their edge portions abutting, and locklng strips secured to the plates near their vertical edges and having their outer edge portions oppositely recurved to interlock.

5. In a cofferdam, a shell formed 0f vertically arranged plates having their edge portions abutting, and locking strips secured to the plates near their vertical edges and having their outer edge portions oppositely recurved to interlock, said locking strips inclosing spaces opposite the joints between the plates to receive a material foi rendering the joints between the plates water tight.

6. ln a coiferdam an inclosing shell formed of a plurality of vertically arranged plates having their edge portions abutting, locking strips having their outer edge portions recurved to interlock and spaced from the plates to inclose spaces, said locking strips having their opposite edge portions placed against the plates, and means for detachably connecting the locking strips t-o the plates.

7 A cofferdam comprising a shell formed of vertically arranged plates having their los:

edges abutting, strips embracing opposite I sides of the plates at the joints and secured along their edges to one of the plates, locking strips placed against the outer sides of the plates andliaving adjacent edge portions reeurved and interlooked and,spaced from the plates, the opposite edge portions of the locking strips touching the plates, and fas tenings detacliably connecting the locking strips to the plates. 1e ln ttinony whereof l aliix my signature 1n presence of two witnesses.

ISAIAH B. LIBBEY.

Vitnesses z A. D. DABNEY, O. L. PRATr. 

